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优化合成路线和工艺,合成目的产物氟噁唑酰胺。以3,5-二氯溴苯为原料,经格氏化,与三氟乙酸甲酯反应得到3’,5’-二氯-2,2,2-三氟苯乙酮;在月桂酸钠的催化下,2-甲基-4-乙酰基苯甲酸与3’,5’-二氯-2,2,2-三氟苯乙酮缩合,脱水,再与盐酸羟胺环化得到关键中间体4-[5-(3,5-二氯苯基)-5-三氟甲基-4,5-二氢异噁唑-3-基]-2-甲基苯甲酸;关键中间体经酰氯化后氨解得到4-[5-(3,5-二氯苯基)-5-三氟甲基-4,5-二氢异噁唑-3-基]-2-甲基苯甲酰胺;然后与原甲酸三甲酯,甲氧基胺盐酸盐反应得到目的产物氟噁唑酰胺。产物结构经核磁共振氢谱确证。该工艺简单经济,条件温和,具有工业化应用前景。 相似文献
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改进了BAH重要中间体3-(2-氨基-2-硫代乙基)苯甲酸甲酯的合成工艺。以苯甲酸甲酯为原料,通过氯甲基化、氰化和硫代三步反应合成3-(2-氨基-2-硫代乙基)苯甲酸甲酯。采用多聚甲醛和氯化氢作为氯甲基化试剂,通过多氯甲基副产物的循环,抑制多氯甲基化副反应,3-氯甲基苯甲酸甲酯收率可达85.3%;在水相中进行氰化反应,3-氰甲基苯甲酸甲酯收率达90.2%;以硫化氢为硫代试剂,在新型水/脒类盐酸盐的溶剂/催化剂体系中,结合滤液循环工艺,3-(2-氨基-2-硫代乙基)苯甲酸甲酯收率可达98.6%;三步反应总收率75.9%。 相似文献
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以乙酰丙酮和丙酰乙酸甲酯为主要原料,经过亚硝化、还原和Knorr成环等反应步骤,合成了多取代吡咯化合物5-甲基-3-乙基-4-乙酰基-2-甲氧羰基吡咯。研究了乙酰丙酮用量,亚硝化反应温度以及亚硝酸钠用量等反应条件对目标化合物产率的影响,确定了最佳的合成反应条件为:乙酰丙酮和丙酰乙酸甲酯摩尔比为1.8∶1.0,亚硝化反应温度为5℃,亚硝酸钠和丙酰乙酸甲酯摩尔比为1.3∶1.0。在给定的最佳合成反应条件下目标化合物的产率可达55%。通过熔点测定、IR和1H NMR等光谱分析手段对化合物进行了表征。 相似文献
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以固体超强酸SO2 -4/TiO2 MoO3 为催化剂 ,通过正丁酸和正戊醇反应合成了丁酸正戊酯 ,探讨了诸因素对收率的影响。合成丁酸正戊酯的最优条件为醇酸物质的量比为 1 5∶1,催化剂用量为反应物料总质量的2 0 % ,反应时间 1 5h。在上述最优条件下 ,以乙醇、丙醇、丁醇、异戊醇和正丁酸为原料合成丁酸系列酯 ,丁酸乙酯的收率为 14 9% ,丁酸丙酯的收率为 4 5 4 % ,丁酸丁酯的收率为 6 8 0 % ,丁酸正戊酯的收率为 97 9% ,丁酸异戊酯的收率为 91 1%。实验表明 :SO2 -4/TiO2 MoO3 具有良好的催化活性。 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria. 相似文献
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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively.
There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized.
High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without
the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of
fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to
achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic
SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve
F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender
particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing,
and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing
or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually
preserves suspension stability during freezing.
Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago,
IL. Tied for first place in The John A. Gordon Best Paper Competition. 相似文献
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Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US
In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae
and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted
in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures
(release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species
(Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species
to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were
exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of
separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles
from the southeastern region of the US. 相似文献
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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed. 相似文献
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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍. 相似文献
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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。 相似文献